Along with its needed effects, propranolol may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention. Although not all of these side effects may occur, if they do occur they may need medical attention. The manufacturer's product labeling should always be consulted for a list of side effects most frequently appearing in patients during clinical studies. Summary. Heartburn is found among people who take Propranolol hydrochloride, especially for people who are female, 60+ old , have been taking the drug for 5 - 10 years, also take medication Fosamax, and have Osteoporosis. Side Effects. See also Warning and Precautions sections. Dizziness, lightheadedness, or tiredness may occur as your body adjusts to the medication. Propranolol with Alcohol. Propranolol and ethanol may have additive effects in lowering your blood pressure. You may experience headache, dizziness, lightheadedness, fainting, and/or changes in pulse or heart rate. Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional. If you notice any other effects, check with your healthcare professional. The manufacturer's product labeling should always be consulted for a list of side effects most frequently appearing in patients during clinical studies. Side Effects. Drug information provided by: IBM Micromedex. Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention. Heartburn and acid reflux are side effects of some common medications. Learn about these heartburn causes and if you could benefit from heartburn medicine. Taking propranolol with other drugs that treat heart rhythm problems may cause more side effects. These include lower heart rate, lower blood pressure, or heart blockage. Your doctor should use.